If the inside of the ear is sore, itchy and swollen, the condition would be a case of otitis externa or otitis media, with otitis externa being more likely. Inflammation of the external ear canal mainly includes external ear canal eczema, external ear canal boils, otitis externa, necrotizing otitis externa and fungal otitis externa, etc. Eczema of the external auditory canal is an allergic inflammation of the skin of the external ear canal caused by a metaplasia. Boils and otitis externa are mainly caused by bacterial infections, while necrotizing otitis externa occurs mainly in immunocompromised people, mainly in elderly diabetic patients, and the development of this disease is more serious and can invade the middle ear, inner ear and the tissues of the skull base, and can even be life-threatening. Fungal otitis externa is mainly caused by unclean ear digging and water ingress in the ear. Acute suppurative otitis media, such as respiratory tract infections, tonsillitis, adenoiditis, rhinitis, and sinusitis, can enter the middle ear through the eustachian tube, causing inflammation in the ear and many uncomfortable symptoms. Acute attacks of chronic otitis media caused by triggering factors can also lead to ear discomfort.